Bug#918764: udev: "udevadm control --reload-rules" kills all processes except init

[Lorenz]

Hi,

Il giorno mer 30 gen 2019 alle ore 11:26 Axel Beckert <abe at debian.org> ha
scritto:

> >His "Actually I'm wrong on this" mail
> >(https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=918764#127) was
> >(and actually still is) confusing me.
>

I'm wrong on the claim that, for example, i can crash a VT session by
executing a 'udevadm' command from the graphic session, or vice versa.
To be more clear, when you read message #122 just ignore those lines:

> ..Final Bonus Weirdness:
> if you start udevd in background in the VT session, then go to the
graphic
> session and prompt a udevadm command from there, it's the VT session that
get crashed.

The rest of the message. i.e. how to trigger the bug and the commit that
introduces this bug in Debian's systemd still holds true to me.


> >But some of the details from his first mail which were not cited in
> >his "Actually I'm wrong on this" mail (mainly "This was introduced in
> >commit e803efca") tell me that this _is_ actually a bug in the udev
> >package.
>

That commit triggered the bug in Debian, but the bug itself was already in
the code
since at least systemd v232-15.
According to my experiments, the culprit is the following:

>when udevd is run in background and it's not detached with it's own
'--daemon' option,
>then a udevadm command is enough to kill everything.

It does not make any sense to me, but that's it.

Regards,
Lorenz
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://alioth-lists.debian.net/pipermail/pkg-systemd-maintainers/attachments/20190130/db784fde/attachment.html>